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Full-Text Articles in Physical Sciences and Mathematics

Investigation Of The Critical Behavior In Mn0.94nb 0.06coge Alloy By Using The Field Dependence Of Magnetic Entropy Change, J C. Debnath, P Shamba, A M. Strydom, Jianli Wang, S X. Dou Jan 2013

Investigation Of The Critical Behavior In Mn0.94nb 0.06coge Alloy By Using The Field Dependence Of Magnetic Entropy Change, J C. Debnath, P Shamba, A M. Strydom, Jianli Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

The critical behaviour of Mn0.94Nb0.06CoGe alloy around the paramagnetic-ferromagnetic phase transition was studied based on the field dependence on magnetic entropy change. By using the obtained exponents, the modified Arrott plot is consistent with that by using conventional method. These critical exponents are confirmed by the Widom scaling relation. Based on these critical exponents, the magnetization, field and temperature data around Tc collapse into two curves obeying the single scaling equation MðH; e)¼ebf6(H/ebþc). The calculated critical exponents not only obey the scaling theory but also anastomose the deduced results from the Kouvel-Fisher method [J. S. Kouvel and M. E. Fisher, …


Phase Gap In Pseudoternary R1-Yry Mn2x 2-Xxx Compounds, Jianli Wang, S J. Kennedy, S J. Campbell, M Hofmann, S X. Dou Jan 2013

Phase Gap In Pseudoternary R1-Yry Mn2x 2-Xxx Compounds, Jianli Wang, S J. Kennedy, S J. Campbell, M Hofmann, S X. Dou

Australian Institute for Innovative Materials - Papers

Our neutron diffraction investigation of PrMn2Ge2−xSix reveals a clear separation into two magnetic phases, canted ferromagnetic (Fmc) and antiferromagnetic (AFmc), between x = 1.0 and 1.2 and a commensurate phase gap in the lattice, due to magnetostrictive distortion. This remarkable magnetoelastic phenomenon is driven by a nonuniform atomic distribution on the X site which in turn produces subtle variations in the local lattice and abrupt changes in the Mn-Mn magnetic exchange interaction. Our results show that coexistence of Fmc and AFmc phases depends on lattice parameter, chemical pressure from the rare-earth and metalloid sites, and …


Reduced Graphene Oxide With Superior Cycling Stability And Rate Capability For Sodium Storage, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Jan 2013

Reduced Graphene Oxide With Superior Cycling Stability And Rate Capability For Sodium Storage, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Sodium ion battery is a promising electrical energy storage system for sustainable energy storage applications due to the abundance of sodium resources and their low cost. In this communication, the electrochemical properties of sodium ion storage in reduced graphene oxide (RGO) were studied in an electrolyte consisting of 1 M NaClO4 in propylene carbonate (PC). The experimental results show that the RGO anode allowed significant sodium ion insertion, leading to higher capacity at high current density compared to the previously reported results for carbon materials. This is due to the fact that RGO possesses higher electrical conductivity and is a …


Preparation And Characterisation Of Graphene Composite Hydrogels, Nicholas J. Whiteside, Gordon G. Wallace, Marc In Het Panhuis Jan 2013

Preparation And Characterisation Of Graphene Composite Hydrogels, Nicholas J. Whiteside, Gordon G. Wallace, Marc In Het Panhuis

Australian Institute for Innovative Materials - Papers

Stable dispersions containing graphene and gellan gum are used to form composite films. Incorporation of graphene into the gellan gum matrix results in mechanical reinforcement and electrical conductivity at low and high graphene loading fractions, respectively. Graphene-containing gellan gum hydrogel films are prepared by immersion of composite films in Ca2+ cross-linking solutions. The resulting hydrogels are electrically conducting and exhibit reinforcement compared to the corresponding gellan gum hydrogels. 2013 Elsevier B.V.


The Nanostructure Of Three-Dimensional Scaffolds Enhances The Current Density Of Microbial Bioelectrochemical Systems, Victoria Flexer, Jun Chen, Bogdan C. Donose, Peter C. Sherrell, Gordon G. Wallace, Jurg Keller Jan 2013

The Nanostructure Of Three-Dimensional Scaffolds Enhances The Current Density Of Microbial Bioelectrochemical Systems, Victoria Flexer, Jun Chen, Bogdan C. Donose, Peter C. Sherrell, Gordon G. Wallace, Jurg Keller

Australian Institute for Innovative Materials - Papers

Bioelectrochemical systems encompass a range of electrochemical systems wherein microorganisms are used as biocatalysts. These range from classical microbial fuel cells to novel microbial electrosynthesis processes. The future of practical applications relies on increased performance. In all cases the development of new electrode materials is essential to overcome the low current densities of bioelectrochemical systems. Here we describe a new biocompatible, highly conductive three-dimensional scaffold electrode, NanoWeb-RVC, with a hierarchical porous structure, synthesized by direct growth of carbon nanotubes on a macroporous substrate. The nanostructure of these electrodes enhances the rate of bacterial extracellular electron transfer while the macrostructure ensures …


Single-Pulse Terahertz Coherent Control Of Spin Resonance In The Canted Antiferromagnet Yfeo3, Mediated By Dielectric Anisotropy, Zuanming Jin, Zoltan Mics, Guohong Ma, Zhenxiang Cheng, Mischa Bonn, Dmitry Turchinovich Jan 2013

Single-Pulse Terahertz Coherent Control Of Spin Resonance In The Canted Antiferromagnet Yfeo3, Mediated By Dielectric Anisotropy, Zuanming Jin, Zoltan Mics, Guohong Ma, Zhenxiang Cheng, Mischa Bonn, Dmitry Turchinovich

Australian Institute for Innovative Materials - Papers

We report on the coherent control of terahertz (THz) spin waves in a canted antiferromagnet yttrium orthoferrite, YFeO3, associated with a quasiferromagnetic (quasi-FM) spin resonance at a frequency of 0.3 THz, using a single-incident THz pulse. The spin resonance is excited impulsively by the magnetic field component of the THz pulse. The intrinsic dielectric anisotropy of YFeO3 in the THz range allows for coherent control of both the amplitude and the phase of the excited spin wave. The coherent control is based on simultaneous generation of two interfering phase-shifted spin waves whose amplitudes and relative phase, dictated by the dielectric …


The Effect Of Dopant Pka And The Solubility Of Corresponding Acid On The Electropolymerisation Of Pyrrole, Eimear M. Ryan, Carmel B. Breslin, Simon E. Moulton, Gordon G. Wallace Jan 2013

The Effect Of Dopant Pka And The Solubility Of Corresponding Acid On The Electropolymerisation Of Pyrrole, Eimear M. Ryan, Carmel B. Breslin, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

In this paper, attempts to dope polypyrrole (PPy) with two small sized anionic drugs, diclofenac sodium salt (NaDF) and valproic acid sodium salt (NaVPA), are described. For PPy doped with DF-, unusual patterns in growth and morphology were observed. During the deposition of the polymer, the rate of electropolymerisation decreased with increasing time and higher applied potentials. The polymer had features of an insulating film, while SEM confirmed the presence of crystal-like shards on the surface of the polymer. Analyses of these crystals indicate them to be drug that may have precipitated out of solution. These findings suggest that insoluble …


Magnetotransport Dependence On The Field Magnitude And Direction In Large Area Epitaxial Graphene Film On Stretchable Substrates, Peite Bao, Wenxian Li, Wai Kong Yeoh, Xiangyuan Cui, J. H. Kim, Yong-Mook Kang, Wenrong Yang, S X. Dou, Simon P. Ringer, Rongkun Zheng Jan 2013

Magnetotransport Dependence On The Field Magnitude And Direction In Large Area Epitaxial Graphene Film On Stretchable Substrates, Peite Bao, Wenxian Li, Wai Kong Yeoh, Xiangyuan Cui, J. H. Kim, Yong-Mook Kang, Wenrong Yang, S X. Dou, Simon P. Ringer, Rongkun Zheng

Australian Institute for Innovative Materials - Papers

We report the magnetotransport properties of large area graphene on stretchable polyethylene terephthalate substrates. At 2 K, weak localization of electrons introduced negative magnetoresistance at low field; a transition to positive magnetoresistance followed as the external field increases. Our results suggest that weak localization contributes to Hall effect at low temperature. At room temperature, only classical Lorentz force contribution can be observed. Angular dependence of the external magnetic field on longitudinal and transverse resistivity is measured to test the interplay between weak localization and Lorentz force contribution. Quantitative simulations based on quantum interference theory produced excellent agreement with the experiments.


Nanocomposites Of Silicon And Carbon Derived From Coal Tar Pitch: Cheap Anode Materials For Lithium-Ion Batteries With Long Cycle Life And Enhanced Capacity, Yun-Xiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Jan 2013

Nanocomposites Of Silicon And Carbon Derived From Coal Tar Pitch: Cheap Anode Materials For Lithium-Ion Batteries With Long Cycle Life And Enhanced Capacity, Yun-Xiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

From energy and environmental consideration, an industrial waste product, coal tar pitch (CTP), is used as the carbon source for Si/AC composite. We exploited a facile sintering method to largely scale up Si/amorphous carbon nanocomposite. The composites with 20 wt.% silicon with PVdF binder exhibited stable lithium storage ability for prolonged cycling. The composite anode delivered a capacity of 400.3 mAh g−1 with a high capacity retention of 71.3% after 1000 cycles. Various methods are used to investigate the reason for the outstanding cyclability. The results indicate that the silicon nanoparticles are wrapped by amorphous SiOx and AC in Si/AC …


Lini0.5mn1.5o4 Spinel Cathode Using Room Temperature Ionic Liquid As Electrolyte, Xuan-Wen Gao, Chuanqi Feng, Shulei Chou, Jia-Zhao Wang, Jia-Zeng Sun, Maria Forsyth, Doug Mcfarlane, Hua-Kun Liu Jan 2013

Lini0.5mn1.5o4 Spinel Cathode Using Room Temperature Ionic Liquid As Electrolyte, Xuan-Wen Gao, Chuanqi Feng, Shulei Chou, Jia-Zhao Wang, Jia-Zeng Sun, Maria Forsyth, Doug Mcfarlane, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

In this study, LiNi0.5Mn1.5O4 (LNMO) nanoparticles were prepared as a 5 V cathode material via a rheological phase method and annealed at different temperatures: 680 ◦C, 750 ◦C, and 820 ◦C. The sample annealed at 750 ◦C shows the best performance. A room temperature ionic liquid (RTIL) containing 1 M lithium bis(trifluoromethanesulfonyl) imide (LiNTf2) in N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl) imide (C4mpyrNTf2) was used as novel electrolyte in conjunction with the LNMO cathodes and their electrochemical properties have been investigated. The results show that the LNMO using RTIL as electrolyte has better coulombic efficiency and comparable discharge capacities to those of the cells …


Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen Jan 2013

Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen

Australian Institute for Innovative Materials - Papers

Graphene based materials coupled with transition metal oxides are promising electrode materials in asymmetric supercapacitors owing to their unique properties which include high surface area, good chemical stability, electrical conductivity, abundance, and lower cost profile over time. In this paper a composite material consisting of graphene oxide exfoliated with microwave radiation (mw rGO), and manganosite (MnO) is synthesised in order to explore their potential as an electrode material. The composite material was characterised by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to explore …


Band Structure, Magnetic, And Transport Properties Of Two Dimensional Compounds Sr2-Xgdxcoo4, Q W Yao, Xiaolin Wang, H Kimura, S X. Dou, Konstantin Konstantinov, Z X. Cheng, F Hong, H Zhao, H Qiu, Kiyoshi Ozawa Jan 2013

Band Structure, Magnetic, And Transport Properties Of Two Dimensional Compounds Sr2-Xgdxcoo4, Q W Yao, Xiaolin Wang, H Kimura, S X. Dou, Konstantin Konstantinov, Z X. Cheng, F Hong, H Zhao, H Qiu, Kiyoshi Ozawa

Australian Institute for Innovative Materials - Papers

The layered perovskite compound Sr2-xGdxCoO 4 has not yet been subjected to detailed study so far. In this report, structures, transport, magnetic properties, and first principle calculations will be reported for the two dimensional compounds Sr 2-xGdxCoO4 (x 0.5, 0.75, 1, 1.25). Rietveld refinement revealed that these compounds are crystallized in K2NiF 4-type structures with space group I4/mmm. It was found that the lattice parameter c decreases as x increases. Through the Curies Weiss fitting of the temperature dependent magnetization, it was found that the Sr 1.25Gd0.75CoO4 sample exhibits a weak ferromagnetic to paramagnetic transition at about 62 K, with …


Substitution Of Y For Pr In Prmn2ge2-The Magnetism Of Pr0.8y0.2mn2ge2, Jianli Wang, S J. Campbell, M Hofmann, S J. Kennedy, M Avdeev, M F. Md Din, R Zeng, Z X. Cheng, S X. Dou Jan 2013

Substitution Of Y For Pr In Prmn2ge2-The Magnetism Of Pr0.8y0.2mn2ge2, Jianli Wang, S J. Campbell, M Hofmann, S J. Kennedy, M Avdeev, M F. Md Din, R Zeng, Z X. Cheng, S X. Dou

Australian Institute for Innovative Materials - Papers

Pr0.8Y0.2Mn2 Ge 2 is found to exhibit four magnetic transitions on decreasing the temperature from the paramagnetic region: (i) paramagnetism to intralayer antiferromagnetism (AFl) at TN intra; (ii) AFl to canted ferromagnetism (Fmc) at TC inter; (iii) Fmc to conical magnetic ordering of the Mn sublattice (Fmi) at Tcc; and (iv) Fmi(Mn) to Fmi(Mn) + F(Pr) at TC Pr. These changes in magnetic structure are discussed in terms of changes in the Mn-Mn separation distances caused by the unit cell contraction and by electronic effects due to replacement of 20% of Pr with Y.


Anisotropy Of Crystal Growth Mechanisms, Dielectricity, And Magnetism Of Multiferroic Bi2femno6 Thin Films, P Liu, Z X. Cheng, Y Du, L Y. Feng, H Fang, Xiaolin Wang, S X. Dou Jan 2013

Anisotropy Of Crystal Growth Mechanisms, Dielectricity, And Magnetism Of Multiferroic Bi2femno6 Thin Films, P Liu, Z X. Cheng, Y Du, L Y. Feng, H Fang, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Epitaxial Bi2FeMnO6 (BFMO) thin films deposited on various Nb:SrTiO3 substrates show that the lattice parameters are very sensitive to epitaxial strains. Compressive and tensile strains are induced to the in-plane lattice constants of the (100) and (111) oriented films, respectively, while that of the (110) oriented thin film stay unstrained. The thin films also exhibit a strongly anisotropic growth habit depending on the substrate. Spiral growth, such as in the (100) BFMO film, is unique in samples prepared by pulsed laser deposition. Extrinsic dielectric constants at low frequencies are attributed to oxygen vacancies via the Maxwell-Wagner effect. All the samples …


Bioengineering Of Articular Cartilage: Past, Present And Future, Ken Ye, Raed Felimban, Simon E. Moulton, Gordon G. Wallace, Claudia Di Bella, Kathy Traianedes, Peter F. M Choong, Damian E. Myers Jan 2013

Bioengineering Of Articular Cartilage: Past, Present And Future, Ken Ye, Raed Felimban, Simon E. Moulton, Gordon G. Wallace, Claudia Di Bella, Kathy Traianedes, Peter F. M Choong, Damian E. Myers

Australian Institute for Innovative Materials - Papers

The treatment of cartilage defects poses a clinical challenge owing to the lack of intrinsic regenerative capacity of cartilage. The use of tissue engineering techniques to bioengineer articular cartilage is promising and may hold the key to the successful regeneration of cartilage tissue. Natural and synthetic biomaterials have been used to recreate the microarchitecture of articular cartilage through multilayered biomimetic scaffolds. Acellular scaffolds preserve the microarchitecture of articular cartilage through a process of decellularization of biological tissue. Although promising, this technique often results in poor biomechanical strength of the graft. However, biomechanical strength could be improved if biomaterials could be …


Evidence For Transformation From Δtc To Δl Pinning In Mgb2 By Graphene Oxide Doping With Improved Low And High Field Jc And Pinning Potential, F X Xiang, X L Wang, X Xun, K S.B De Silva, Y X. Wang, S X. Dou Jan 2013

Evidence For Transformation From Δtc To Δl Pinning In Mgb2 By Graphene Oxide Doping With Improved Low And High Field Jc And Pinning Potential, F X Xiang, X L Wang, X Xun, K S.B De Silva, Y X. Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Flux pinning mechanism of graphene oxide (GO) doped MgB2 has been systematically studied. In the framework of the collective pinning theory, a B-T phase diagram has been constructed. By adjusting the GO doping level, the pinning mechanism in MgB2 transformed from transition temperature fluctuation induced pinning, δTc pinning, to mean free path fluctuation induced pinning, δl pinning, is observed. Furthermore, in terms of the thermally activated flux flow model, the pinning potential in high field (B > 5 T) is enhanced by GO doping. The unique feature of GO is the significant improvement of both low field Jc and high field …


A Hybrid Electrolyte Energy Storage Device With High Energy And Long Life Using Lithium Anode And Mno2 Nanoflake Cathode, Shulei Chou, Yun-Xiao Wang, Jiantie Xu, Jia-Zhao Wang, Hua-Kun Liu, S X. Dou Jan 2013

A Hybrid Electrolyte Energy Storage Device With High Energy And Long Life Using Lithium Anode And Mno2 Nanoflake Cathode, Shulei Chou, Yun-Xiao Wang, Jiantie Xu, Jia-Zhao Wang, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

A hybrid electrolyte energy storage system combining the features of supercapacitors and lithium batteries has been constructed. It consists of MnO2 nanoflakes in 1 M Li2SO4 aqueous electrolyte as the cathode and lithium foil in ionic liquid (1 M lithium bis(trifluoromethanesulfonyl)imide (LiNTf2) in N-methyl-N-propyl pyrrolidinium bis(trifluoromethanesulfonyl)imide ([C(3)mpyr][NTf2])) electrolyte as the anode, separated by a lithium super ionic conductor glass ceramic film (LiSICON). This system shows the advantages of both a supercapacitor (long cycle life) and a lithium battery (high energy), as well as low cost and improved safety due to the combination of ionic liquid and ceramic solid state electrolyte …


A Merocyanine-Based Conductive Polymer, Klaudia K. Wagner, Michele Zanoni, Anastasia Elliott, Pawel W. Wagner, Robert P. Byrne, Larisa Florea, Dermot Diamond, Keith Gordon, Gordon G. Wallace, David L. Officer Jan 2013

A Merocyanine-Based Conductive Polymer, Klaudia K. Wagner, Michele Zanoni, Anastasia Elliott, Pawel W. Wagner, Robert P. Byrne, Larisa Florea, Dermot Diamond, Keith Gordon, Gordon G. Wallace, David L. Officer

Australian Institute for Innovative Materials - Papers

We report the first example of a conducting polymer with a merocyanine incorporated into the polymer backbone by electropolymerisation of a spiropyran moiety covalently linked between two alkoxythiophene units. Utilising the known metal coordination capabilities of merocyanines, introduction of cobalt ions into the electropolymerisation led to an enhancement of the conductivity, morphology and optical properties of the polymer films.


Surface Properties And Interaction Forces Of Biopolymer-Doped Conductive Polypyrrole Surfaces By Atomic Force Microscopy, Jani M. Pelto, Suvi P. Haimi, Aliisa S. Siljander, Susanna S. Miettinen, Kirsi M. Tappura, Michael J. Higgins, Gordon G. Wallace Jan 2013

Surface Properties And Interaction Forces Of Biopolymer-Doped Conductive Polypyrrole Surfaces By Atomic Force Microscopy, Jani M. Pelto, Suvi P. Haimi, Aliisa S. Siljander, Susanna S. Miettinen, Kirsi M. Tappura, Michael J. Higgins, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Surface properties and electrical charges are critical factors elucidating cell interactions on biomaterial surfaces. The surface potential distribution and the nanoscopic and microscopic surface elasticity of organic polypyrrole-hyaluronic acid (PPy-HA) were studied by atomic force microscopy (AFM) in a fluid environment in order to explain the observed enhancement in the attachment of human adipose stem cells on positively charged PPy-HA films. The electrostatic force between the AFM tip and a charged PPy-HA surface, the tip-sample adhesion force, and elastic moduli were estimated from the AFM force curves, and the data were fitted to electrostatic double-layer and elastic contact models. The …


Polypyrrole Doped With Redox-Active Poly(2-Methoxyaniline-5-Sulfonic Acid) For Lithium Secondary Batteries, Yang Yang, Caiyun Wang, Syed A. Ashraf, Gordon G. Wallace Jan 2013

Polypyrrole Doped With Redox-Active Poly(2-Methoxyaniline-5-Sulfonic Acid) For Lithium Secondary Batteries, Yang Yang, Caiyun Wang, Syed A. Ashraf, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Polypyrrole is a promising electrode material for flexible/bendable energy storage devices due to its inherent fast redox switching, mechanical flexibility, easy processability and being environmentally benign. However, its low attainable capacity limits its practical applications. Here, we synthesise a polypyrrole/poly(2-methoxyaniline-5-sulfonic acid) (PPy/PMAS) composite by incorporating redox-active PMAS into a PPy matrix via an electropolymerization method. For comparison, polypyrrole containing the electrochemically inert dopant p-toluenesulfonate (PPy-pTS) was prepared under the same conditions. The resultant PPy/PMAS film shows greatly improved electrochemical properties by harnessing the contribution from PMAS, i.e. higher specific capacity, better rate capability and improved cycling stability when used as …


Highly Water-Soluble Magnetic Iron Oxide (Fe3o4) Nanoparticles For Drug Delivery: Enhanced In Vitro Therapeutic Efficacy Of Doxorubicin And Mion Conjugates, Muhammad Irfan Majeed, Qunwei Lu, Wei Yan, Zhen Li, Irshad Hussain, Muhammad Nawaz Tahir, Wolfgang Tremel, Bien Tan Jan 2013

Highly Water-Soluble Magnetic Iron Oxide (Fe3o4) Nanoparticles For Drug Delivery: Enhanced In Vitro Therapeutic Efficacy Of Doxorubicin And Mion Conjugates, Muhammad Irfan Majeed, Qunwei Lu, Wei Yan, Zhen Li, Irshad Hussain, Muhammad Nawaz Tahir, Wolfgang Tremel, Bien Tan

Australian Institute for Innovative Materials - Papers

We report a simple one step protocol for the preparation of fairly monodisperse and highly water-soluble magnetic iron oxide nanoparticles (MIONs) through a co-precipitation method using a novel multifunctional, biocompatible and water-soluble polymer ligand dodecanethiol-polymethacrylic acid (DDT-PMAA). DDT-PMAA owing to its several intrinsic properties, not only efficiently controls the size of the MIONs but also gives them excellent water solubility, long time stability against aggregation and oxidation, biocompatibility and multifunctional surface rich in thioether and carboxylic acid groups. The molecular weight and concentration of the polymer ligand were optimized to produce ultrasmall (4.6 +/- 0.7 nm) MIONs with high magnetization …


'Laser Chemistry' Synthesis, Physicochemical Properties, And Chemical Processing Of Nanostructured Carbon Foams, Andres Seral-Ascaso, Rosa Garriga, Maria Luisa Sanjuan, Joselito M. Razal, Ruth Lahoz, Mariano Laguna, German F. De La Fuente, Edgar Munoz Jan 2013

'Laser Chemistry' Synthesis, Physicochemical Properties, And Chemical Processing Of Nanostructured Carbon Foams, Andres Seral-Ascaso, Rosa Garriga, Maria Luisa Sanjuan, Joselito M. Razal, Ruth Lahoz, Mariano Laguna, German F. De La Fuente, Edgar Munoz

Australian Institute for Innovative Materials - Papers

Laser ablation of selected coordination complexes can lead to the production of metal-carbon hybrid materials, whose composition and structure can be tailored by suitably choosing the chemical composition of the irradiated targets. This 'laser chemistry' approach, initially applied by our group to the synthesis of P-containing nanostructured carbon foams (NCFs) from triphenylphosphine-based Au and Cu compounds, is broadened in this study to the production of other metal-NCFs and P-free NCFs. Thus, our results show that P-free coordination compounds and commercial organic precursors can act as efficient carbon source for the growth of NCFs. Physicochemical characterization reveals that NCFs are low-density …


Aqueous Dispersions Of Reduced Graphene Oxide And Multi Wall Carbon Nanotubes For Enhanced Glucose Oxidase Bioelectrode Performance, Willo Grosse, Joffrey Champavert, Sanjeev Gambhir, Gordon G. Wallace, Simon E. Moulton Jan 2013

Aqueous Dispersions Of Reduced Graphene Oxide And Multi Wall Carbon Nanotubes For Enhanced Glucose Oxidase Bioelectrode Performance, Willo Grosse, Joffrey Champavert, Sanjeev Gambhir, Gordon G. Wallace, Simon E. Moulton

Australian Institute for Innovative Materials - Papers

Aqueous dispersions of reduced graphene oxide (rGO) and multi walled carbon nanotubes (MWCNT) were fabricated through a modified chemical reduction method. The significant advantage of the method developed here is the omission of any stabilising compound or organic solvent to obtain stable rGO-MWCNT dispersions. Significantly biological entities, in this case the enzyme glucose oxidase (GOx), can be successfully incorporated into the dispersion. These dispersions were characterised using XPS, SEM, zeta potential and particle size measurements which showed that the dispersion stability is not sacrificed with the addition of GOx, and significantly, the electrical properties of the rGO and MWCNTs are …


Novel Nanographene/Porphyrin Hybrids-Preparation, Characterization, And Application In Solar Energy Conversion Schemes, Daniel Kiessling, Ruben D. Costa, Georgios Katsukis, Jenny Malig, Fabian Lodermeyer, Sebastian Feihl, Alexandra Roth, Leonie Wibmer, Matthias Kehrer, Michel Volland, Pawel W. Wagner, Gordon G. Wallace, David L. Officer, Dirk M. Guldi Jan 2013

Novel Nanographene/Porphyrin Hybrids-Preparation, Characterization, And Application In Solar Energy Conversion Schemes, Daniel Kiessling, Ruben D. Costa, Georgios Katsukis, Jenny Malig, Fabian Lodermeyer, Sebastian Feihl, Alexandra Roth, Leonie Wibmer, Matthias Kehrer, Michel Volland, Pawel W. Wagner, Gordon G. Wallace, David L. Officer, Dirk M. Guldi

Australian Institute for Innovative Materials - Papers

Four novel nanographene/porphyrin hybrids were prepared, characterized, and probed in solar energy conversion schemes. Exfoliation of graphite by means of immobilizing four different porphyrins onto the basal plane of graphene is accompanied by distinct electronic interactions in both the ground and the excited states. In the ground state, a strong loss in oscillator strength goes hand-in-hand with a notable broadening of the porphyrin transitions and, as such, attests to the shift of electron density from the electron donating porphyrins to nanographene. In the excited state, a nearly quantitative quenching of the porphyrin fluorescence is indicative of full charge transfer. The …


Evaluation Of Encapsulating Coatings On The Performance Of Polypyrrole Actuators, Sina Naficy, Nicholas Stoboi, Philip G. Whitten, Geoffrey M. Spinks, Gordon G. Wallace Jan 2013

Evaluation Of Encapsulating Coatings On The Performance Of Polypyrrole Actuators, Sina Naficy, Nicholas Stoboi, Philip G. Whitten, Geoffrey M. Spinks, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Conjugated polymer actuators are electroactive materials capable of generating force and movement in response to an applied external voltage. Many potential biomedical and industrial applications require these actuators to operate in a liquid environment. However, immersion of uncoated conducting polymer actuators in non-electrolyte liquids greatly reduces their operating lifetime. Here, we demonstrate the use of spray coating as an effective and simple method to encapsulate polypyrrole (PPy) tri-layer bending actuators. Poly(styrene-b-isobutylene-b-styrene) (SIBS) was used as an encapsulating, compliant spray coating on PPy actuators. A significant enhancement in actuator lifetime in both air and water was observed by encapsulating the actuators. …


Thermoelectric Properties Of Ca3co4o9 And Ca2.8bi0.2co4o9 Thin Films In Their Island Formation Mode, Priyanka Jood, Germanas Peleckis, Xiaolin Wang, S X. Dou Jan 2013

Thermoelectric Properties Of Ca3co4o9 And Ca2.8bi0.2co4o9 Thin Films In Their Island Formation Mode, Priyanka Jood, Germanas Peleckis, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Ca3Co4O9 and Ca2.8Bi 0.2Co4O9 thin films were fabricated on LaAlO3 (LAO) substrate using pulsed laser deposition technique and were studied for their thermoelectric (TE) properties in Stranski-Krastanov mode for the first time. The thin films consisted of 3D clusters/islands on a 14-nm thick 2D layer with cluster density being higher for Ca 2.8Bi0.2Co4O9 thin films. The clusters also represent areas of dislocation and therefore act as carrier scattering centers, which leads to a temperature-activated type conductivity. Seebeck coefficient as high as 136 and 163 u V/K was measured for the Ca 3Co4O9 and Ca2.8Bi 0.2Co4O9 thin films, respectively, which is …


Rational Design Of P-Type Thermoelectric Pbte: Temperature Dependent Sodium Solubility, Sima Aminorroaya-Yamini, Teruyuki Ikeda, Aaron Lalonde, Yanzhong Pei, S X. Dou, G. Jeffrey Snyder Jan 2013

Rational Design Of P-Type Thermoelectric Pbte: Temperature Dependent Sodium Solubility, Sima Aminorroaya-Yamini, Teruyuki Ikeda, Aaron Lalonde, Yanzhong Pei, S X. Dou, G. Jeffrey Snyder

Australian Institute for Innovative Materials - Papers

We develop a solid understanding of the termperature-dependent solubility of sodium p-type PbTe, the most efficient thermoelectric material. The maximum solubility of socium telluride (NaTe) in PbTe is measured to be 1.4+0.3 at percent and the heat of solution is evaluated and that addresses fundamental issues regarding the formation of nano-precipitates.


A Significant Improvement In Both Low- And High-Field Performance Of Mgb2 Superconductors Through Graphene Oxide Doping, K S B De Silva, S H Aboutalebi, Xun Xu, Xiaolin Wang, W X Li, Konstantin Konstantinov, S X. Dou Jan 2013

A Significant Improvement In Both Low- And High-Field Performance Of Mgb2 Superconductors Through Graphene Oxide Doping, K S B De Silva, S H Aboutalebi, Xun Xu, Xiaolin Wang, W X Li, Konstantin Konstantinov, S X. Dou

Australian Institute for Innovative Materials - Papers

The effects of graphene oxide (GO) doping on the superconducting properties of MgB2 were studied using bulk samples made by the diffusion method. Homogeneous dispersions of GO in tetrahydrofuran were obtained through a novel synthesis method, which is then chemically doped with MgB2. It was found that GO doping significantly improves the critical current density, under both low and high magnetic fields, which distinguishes GO from all the other elements doped into MgB2 so far. 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.


Ti Substitution For Mn In Mncoge - The Magnetism Of Mn0.9ti0.1coge, Jianli Wang, P Shamba, W D. Hutchinson, M F. Md Din, J C. Debnath, M Avdeev, R Zeng, S J. Kennedy, S J. Campbell, S X. Dou Jan 2013

Ti Substitution For Mn In Mncoge - The Magnetism Of Mn0.9ti0.1coge, Jianli Wang, P Shamba, W D. Hutchinson, M F. Md Din, J C. Debnath, M Avdeev, R Zeng, S J. Kennedy, S J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

Bulk magnetization measurements (5-320 K; 0-8T) reveal that below room temperature Mn0.9Ti0.1CoGe exhibits two magnetic phase transitions at ~178 K and ~280 K. Neutron diffraction measurements (3-350K) confirm that the transition at ~178K is due to the structural change from the low-temperature orthorhombic TiNiSi-type structure to the higher temperature hexagonal Ni2In-type structure while the transition at ~280K originates from the transition from feromagnetism to paramagnetism.


Multifunctional Conducting Fibres With Electrically Controlled Release Of Ciprofloxacin, Dorna Esrafilzadeh, Joselito M. Razal, Simon E. Moulton, Elise M. Stewart, Gordon G. Wallace Jan 2013

Multifunctional Conducting Fibres With Electrically Controlled Release Of Ciprofloxacin, Dorna Esrafilzadeh, Joselito M. Razal, Simon E. Moulton, Elise M. Stewart, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

We hereby present a new method of producing coaxial conducting polymer fibres loaded with an antibiotic drug that can then be subsequently released (or sustained) in response to electrical stimulation. The method involves wet-spinning of poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) fibre, which served as the inner core to the electropolymerised outer shell layer of polypyrrole (Ppy). Ciprofloxacin hydrochloride (Cipro) was selected as the model drug and as the dopant in the Ppy synthesis. The release of Cipro in phosphate buffered saline (PBS) from the fibres was controlled by switching the redox state of Ppy.Cipro layer. Released Cipro under passive and stimulated conditions …